Using Industry 4.0 Tools to Maintain Maximum Sheet Consistency Out of the Press Section

Minor variations in the papermaking process such as starch, vacuum, life of clothing, stock quality/refining, variability in OCC can have important effects on dewatering in the forming and press sections, which in turn determines the sheet moisture entering the dryer section.    Monitoring sheet consistency at key locations prior to the dryer section is key in maintaining optimal process control across all grades.   Grab samples, if permissible from a safety standpoint, can provide useful information but data is sporadic and there is a significant delay between the time of sampling and acquiring results.  Highly accurate, online measurement of sheet consistency is now possible using advanced microwave, non-radioactive instruments.  These instruments can be located in the forming section, press section, and at the start of the first dryer section and provide continuous, real-time data. 
 
Studies have been performed where sheet consistency data is collected from these sensors and the reel scanner over a prolonged period of time.  The relative dewatering by forming, pressing and drying will vary over time, even within the same grade, due to those variables described above.  It can be shown that there is a direct relationship between press, forming and dryer section dewatering.  This relationship can be seen graphically, with the process conditions that result in minimized dryer section dewatering contribution clearly evident. This presentation will describe a methodology for using software tools and Industry 4.0 practices to identify specific areas of attention when the process drifts from optimal state and, which processes can be controlled in a closed loop to minimize specific steam consumption.  

Learning Outcomes:

Understand the type and use of instrumentation required to set up Industry 4.0 controls on a paper machine to maintain maximum solids entering the dryer section

Spekaers: Luca Canali and Lawrence Yane